What is the note on the 2nd fret of the 2nd string?

To identify the note on the 2nd fret of the 2nd string (which is the B string), you start with understanding the notes on the guitar fretboard. The open 2nd string is tuned to B. When you press down on the 2nd fret, you raise the pitch of that string by two half steps.

The first half step from B is C, and the second half step is C# (C-sharp). Therefore, the note on the 2nd fret of the 2nd string is C# and not Cmaj, G, A, or C.

Being familiar with the chromatic scale (where each fret up the neck of the guitar represents a half step) is essential for determining notes accurately across the fretboard.